As an effort to reach the Healthy People 2010 and Healthy People 2020 goals of achieving health equity, eliminating disparities, and improving the health of all groups, the National Cancer Institute (NCI) established a contract to produce two monographs, which compared and reviewed various disparity indices. HD*Calc is a statistical software created as an extension of the two monographs, and was designed so that public health practitioners and researchers can examine and compare different disparities indices using their own data. Two methods of measuring the uncertainty of the estimates are currently implemented in the software: a Taylor series linearization method and a Bootstrap method. No evaluation study has been done to examine the coverage property (how often the confidence interval can cover the true value if the sample is repeated many times) of the two methods. There is a statistical need of practical importance to evaluate the coverage property of the current methods.